public class L746 {

    public static void main(String[] args) {

        int[] cost = {10, 15, 20};
        int stairs = new Solution().minCostClimbingStairs(cost);
        System.out.println(stairs);
    }

    static class Solution {
        public int minCostClimbingStairs(int[] cost) {
            int[] dp = new int[cost.length + 1];

            dp[0] = 0;
            dp[1] = 0;

            for (int i = 2; i <= cost.length; i++) {
                dp[i] = Math.min(dp[i - 1] + cost[i - 1], dp[i - 2] + cost[i - 2]);
            }

            return dp[dp.length - 1];
        }
    }
}
